Panel fastener

ABSTRACT

An elongate fastener is provided for securing a pair of panels together wherein the panels includes respective bores therein. Each end of the fastener includes an expansible end portion thereon which is arranged to be received within the respective bore. A wedge member is mounted within each expansible end portion for longitudinal sliding movement between a disengaged position and an engaged position wherein the expansible end portions are expanded relative to the disengaged position. An actuator is located centrally between the expansible end portions for pivotal movement about an actuator axis which lies perpendicularly to a longitudinal axis of the fastener. The fastener permits a pair of panels to be mounted with one end of one panel abutted against the other panel wherein the actuator is accessible from a recessed installation aperture on an inner face of one of the panels. The resulting joint is secure while being hidden from view using a one-piece fastener.

FIELD OF THE INVENTION

[0001] This invention relates to a fastener for fastening a pair ofobjects together. It has particular application to the coupling ofpanels, for example those used in furniture.

BACKGROUND

[0002] Various types of fasteners are used for assembly of furniture andthe like wherein it is desirable to make use of a fastener which isstrong yet simple and quick to use. This includes the commercialassembly of cabinets and the like as well as assembly of furniture atthe factory by professionals. The ready to assemble (RTA) furnitureindustry is one particular example involving furniture which is sold tothe customer in a disassembled form that makes use of appropriatefasteners such that the customer is able to assemble the furniture intheir homes using conventional tools. Fasteners designed for this useare preferably easy to use by the general public, while being secure andwell hidden upon assembly of the RTA furniture.

[0003] An example of a fastener for RTA furniture is illustrated inEuropean Application No. 0 949 424 to Hafele GmbH &CO. That applicationdiscloses a fastener for use in mounting a pair of panels togetherwherein the fastener includes a first expansible wedge member arrangedto mount in a bore in one of the panels and a second expansible wedgemember arranged to mount in a bore in the other panel. An actuator forthe wedges is located at one end of the fastener such that the secondwedge member is located centrally on the fastener and oriented such thatupon assembly, an apex of the second wedge member is directed inwardlytowards the panel securing the second wedge member therein. This occursdue to the location of the actuator at one end of the fastener whichrequires both wedges to be oriented in the same direction in order tomake use of a common actuator. In this orientation, expansion of thesecond wedge member causes a wedging action to urge the fastener out ofthe panel instead of drawing the panels together. Furthermore, the firstand second wedge members require different bore sizes in which to bereceived which results in added tooling and manufacturing costs whenforming the panels.

SUMMARY

[0004] According to one aspect of the present invention there isprovided a method of joining two objects with respective fastenerreceiving bores therein, the method comprising:

[0005] providing an elongate fastener assembly with opposite ends, thefastener assembly comprising first and second elongate fastener elementsarranged side by side;

[0006] inserting the opposite ends of the fastener assembly into therespective bores; and

[0007] displacing the first and second fastener elements relative to oneanother to expand the ends of the fastener assembly thereby griping thebores.

[0008] The movement of the two elements relative to one another thuscauses the expansion of the ends of the fastener assembly for anchoringpurposes.

[0009] According to another aspect of the present invention there isprovided a fastener for securing together a pair of opposing objectshaving respective bores therein, the fastener comprising:

[0010] an elongate fastener assembly having first and second expansibleportions at respective ends thereof for being slideably received withinthe respective bores;

[0011] first and second wedge members mounted adjacent the respectiveends of the fastener assembly for engagement with the respective firstand second expansible portions thereof, the wedge members and therespective expansible portions being mounted for sliding movementrelative to one another in a longitudinal direction of the fastenerassembly between a disengaged position and an engaged position whereinthe wedge members are wedged within the respective expansible portionsof the fastener assembly such that the expansible portions of thefastener assembly are expanded in a radial direction relative to thedisengaged position; and

[0012] an actuator mounted on the fastener assembly for rotation aboutan actuator axis extending transversely to the elongate fastenerassembly at a location spaced between the wedge members, the actuatorbeing coupled to the wedge members respectively for displacing the wedgemembers relative to the expansible portions between the engaged anddisengaged positions as the actuator is rotated relative to the fastenerassembly.

[0013] The expansible portions of the fastener assembly may be mountedfor longitudinal sliding movement relative to one another and coupled tothe actuator to be displaced towards one another in moving from thedisengaged position to the engaged position.

[0014] The actuator may be a cam mounted for rotation about an actuatoraxis. Each wedge member may be associated with a cam follower for urgingthe wedge member into the engaged position as the cam is rotated.

[0015] The wedge members may fixed in relation to the fastener assemblyand the expansible portions slideably mounted on the fastener assemblyfor movement towards each other as the expansible portions are displacedfrom the disengaged position to the engaged position. Alternatively, theexpansible portions may be fixed in relation to the fastener assemblyand the wedge members slideably mounted for movement away from eachother as they are displaced from the disengaged position to the engagedposition.

[0016] In one particularly advantageous embodiment, the fastenerassembly has two elongate elements, each including respective ones ofthe expansible portions and the wedge members. The two elements areslideable relative to one another for displacing the wedge membersrelative to the respective expansible portions between the disengagedand the engaged positions.

[0017] In another embodiment, a flexible tension member is coupledbetween the two wedge members and the actuator is a rotatable spindlehaving an aperture through which the tension member is threaded so thatrotation of the spindle causes the tension member to be wrapped aboutthe spindle, drawing the wedge members longitudinally towards eachother.

[0018] The fastener may include a lock for resisting reverse rotation ofthe spindle and unwinding of the tension member.

[0019] The wedge members may be substantially conical in shape, with aninner surface of each expansible portion having a mating conicalsurface.

[0020] According to another aspect of the present invention there isprovided a fastener for securing together opposing objects havingrespective bores therein, the fastener comprising:

[0021] a pair of elongate members each having a wedge at a first end andan expansible portion at a second end thereof, the wedge of each memberbeing located adjacent the expansible portion of other member, spacedlongitudinally inward therefrom in a disengaged position, the elongatemembers being slideable relative to one another in a longitudinaldirection of the members from the disengaged position to an engagedposition wherein the wedge of each member is wedged within theexpansible portion of the other member such that the expansible portionsare expanded radially relative to the disengaged position; and

[0022] stop means associated with each of the members for engaging therespective objects as the ends of the members are inserted into therespective bores, whereby on displacement of the objects towards oneanother, the objects engage the stop means to displace the expansibleends inwardly towards each other and into the engaged position thereof.

[0023] According to a further aspect of the present invention there isprovided fastener for coupling two objects with respective fastenerreceiving bores therein, the fastener comprising an elongate fastenerassembly with opposite ends for insertion into the respective bores inthe two objects, the assembly including:

[0024] first and second elongate elements positioned side by side andrelatively movable between a disengaged position and an engaged positionin which the ends of the fastener assembly are expanded transversely toengage the respective bores; and

[0025] a retainer for retaining the first and second elements in theengaged position.

[0026] The retainer is particularly useful in those embodiments wherethere is no actuator per se incorporated into the fastener, and therelative movement of the first and second elements of the fastenerassembly is caused either by an external tool that does not form part ofthe fastener or by engagement of the fastener elements with objects tobe joined as they are moved together. In one such embodiment the twoelements are longitudinally tapered and slide over one another as wedgesas they are longitudinally displaced relative to one another. Thisexpands the lateral dimension of the fastener to engage the bores in thetwo objects being coupled.

[0027] In embodiments without an actuator, one of the elements may havea transverse through aperture and the other a cavity confronting theaperture. This allows a lever, for example a screwdriver to be insertedthrough the aperture to engage the cavity so that a prying action willmove the two elements relative to one another.

[0028] The retainer may be one or more projections on one of the twoelements and mating recesses in the other element, with the projectionshaving inclined leading faces to serve as a kind of ratchet mechanism.

[0029] In other embodiments, the fastener includes an actuator that isused to separate the two elements transversely. This may be a screwthreaded into one of the elements and engaging the other. In this case,the two elements move transversely relative to one another in movementbetween the disengaged and engaged position. The threaded actuator thenserves as the retainer.

[0030] According to another aspect of the present invention there isprovided a fastener for coupling two objects with respective fastenerreceiving bores therein, the fastener comprising an elongate fastenerassembly with opposite ends for insertion into the respective bores inthe two objects, the ends being transversely expandable to grip therespective bores and each end having teeth on the periphery thereof,wherein the teeth are helically oriented ribs.

[0031] The helical teeth allow the fastener to be screwed into the boresbefore expansion of the fastener assembly ends.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In the accompanying drawings, which illustrate exemplaryembodiments of the present invention:

[0033]FIG. 1 is an isometric view of a first embodiment of the presentinvention shown as it would be installed between a pair of panels to bejoined.

[0034]FIG. 2 is a sectional side view of the fastener of FIG. 1 in adisengaged position.

[0035]FIG. 3 is a sectional view along the line 3-3 of FIG. 2 in anengaged position.

[0036]FIG. 4 is a side view of a different embodiment of the fasteneraccording to the present invention shown in a disengaged position.

[0037]FIG. 5 is a side view of the fastener of FIG. 4 shown in theengaged position.

[0038]FIG. 6 is a partly sectional view along the line 6-6 of FIG. 5.

[0039]FIG. 7 is a top plan view of a further embodiment of the presentinvention shown in a disengaged position.

[0040]FIG. 8 s a top plan view of the fastener of FIG. 7 shown in anengaged position.

[0041]FIG. 9 is an isometric view of yet another embodiment of thepresent invention.

[0042]FIG. 10 is an exploded side view of the fastener according to FIG.9.

[0043]FIG. 11 is a top view along the line 11-11 of FIG. 10.

[0044]FIG. 12 is an isometric view of a further embodiment of thefastener shown mounting two panels in an edge to edge configuration.

[0045]FIG. 13 is a sectional top view of another embodiment of thefastener.

[0046]FIG. 14 is an isometric view of another embodiment of the presentinvention;

[0047]FIG. 15 is a axial cross section of the embodiment of FIG. 14;

[0048]FIG. 16 is a side elevation of a further embodiment of the presentinvention;

[0049]FIG. 17 is a aide view of another embodiment of the presentinvention;

[0050]FIG. 18 is a exploded view of another embodiment of the presentinvention;

[0051]FIG. 19 is a side view of the embodiment of FIG. 18;

[0052]FIG. 20is a side view of a fastener assembly end with helicalteeth;

[0053]FIG. 21 is a partial cross section of a fastener assemblyincluding an inclined cam actuator;

[0054]FIG. 22 is an isometric view of a fastener assembly end showingcertain tooth configurations;

[0055]FIG. 23 is a cross section along line 23-23 of FIG. 22; and

[0056]FIG. 24 is a plan view of a one piece molding for use in afastener assembly.

DETAILED DESCRIPTION

[0057] Referring to the accompanying drawings, there is illustrated afastener generally indicated by reference numeral 10. The fastener isfor use in joining a pair of opposing panels 12 each having a respectivebore 14 therein. In the arrangement of FIG. 1, one of the panels shownis an edge bored panel while the opposing surface comprises a face boredpanel wherein each bore is arranged to receive an end of the fastenertherein for joining the panels. This is a typical arrangement whensecuring ready to assembly furniture and the like.

[0058] In a first embodiment of the present invention as shown in FIGS.1 through 3, the fastener 10 includes an elongate fastener assembly 16having an expansible portion 18 located at each end of the fastenerassembly. The expansible portions are generally cylindrical extensionsof the fastener assembly having a gripping outer surface 20 for engagingwithin one of the bores 14 of the panels to be joined. The expansibleportions are arranged to be expanded in a radial direction onceinstalled in the respective bores to secure the fastener within thebore.

[0059] An inner face 22 of each expansible portion is generally conicalin shape, with the inner face 22 of the expansible portions taperedinwards towards each other. Each expansible portion 18 includes at leastone longitudinally extending expansion slot 24 to permit lateralexpansion in a direction indicated by arrows 26.

[0060] A pair of wedge members 28 are mounted within the respectiveexpansible portions 18 for sliding movement therein. Each wedge member28 is frustoconical in shape, tapering inwardly towards each other formating with the respective inner faces 22 of the expansible portions 18.As shown in the disengaged position of FIG. 2 the wedge members matewith the respective expansible portions with the expansible portionsbeing in a relaxed position with a diameter substantially equal to thatof the fastener assembly 16. As the wedge members are displaced inwardlyas shown in the engaged position of FIG. 3, the members 28 act as wedgesto expand the expansion slots 24 of the respective expansible portions18 thus expanding the portions 18 in the direction of arrow 26.

[0061] A tension member 30 in the form of a flexible wire extendsbetween the wedge members 28 and has the wedge members fastened to itsopposite ends. In one embodiment the wedge member is hollow and has anaperture at its apex through which the wire is threaded. A ball ofgreater diameter than the aperture is mounted on the end of the wireinside the wedge member.

[0062] An actuator is provided in the form of a spindle 32 which ismounted centrally within the fastener assembly for rotation about atransverse actuator axis 34 substantially perpendicularly to thelongitudinal axis of the fastener assembly and to the direction ofexpansion indicated by arrow 26. An outer end 36 of the spindle includesa conventional socket thereon to be engaged to a screwdriver, forexample, to rotate the spindle 32 as desired.

[0063] A boss 38 mounts the inner end 40 of the spindle for rotation inthe assembly. An aperture is provided in the fastener assembly forreceiving the outer end 36 of the spindle therethrough to permit accessto the socket thereon. In use the outer end 36 of the spindle 32 isaligned with an installation aperture 42 in an outer surface 44 of oneof the panels 12 to be joined together as shown in FIG. 1.

[0064] The spindle 32 includes a diametric aperture 46 through which thetension member 30 is threaded. In this arrangement, as the spindle 32 isrotated, the tension member 30 is wrapped around the spindle 32 as shownin FIG. 3 for tensioning the tension member and drawing the wedgemembers 28 inwardly to expand the respective expansible portions 18.

[0065] In use two panels 12 are oriented to be mounted together whereinone of the panels includes an installation aperture 42 as shown inFIG. 1. The fastener is inserted into the respective bores 14 such thatthe actuator axis 34 is aligned with the installation aperture 42 suchthat the socket on the outer end of the spindle 32 is accessible oncethe fastener has been inserted into the respective bores.

[0066] Rotation of the spindle as shown in FIG. 3 will displace thewedge members from the disengaged position to the engaged position, thusdisplacing two diametric halves of the respective expansible portion 18in the direction indicated by arrow 26 along a diameter thereof whichlies substantially parallel to the surface of the respective panels 12.The compression force which secures the fastener within the respectivebores is thus directed in a plane along the surface of the panel asopposed to expanding the expansible portions in a direction extendingtransversely to the surfaces of the panels 12 which would result inpuckering of the faces of the panels 12 resulting in an undesirablefinish when used on furniture and the like.

[0067] The use of a flexible tension member allows unlimited travel ofthe wedges as opposed to the fixed amount of displacement when using acam actuator. This permits less restrictive tolerances in bore sizes andbore placement when forming panels to be mounted together using thefasteners of the present invention.

[0068] In an alternate embodiment as shown in FIGS. 4 through 6 there isprovided an elongate tubular housing 50. The housing includes twopointed ends 52 such that the assembled fastener assembly includes ahollow interior having tapered ends defining respective wedge members 54at respective ends thereof.

[0069] A pair of expansible end portions 56 are mounted on therespective ends of the housing for sliding movement relative to thehousing and the wedge members 54 which are integrally formed thereon.Each expansible end portion 56 comprises a cylindrical plug formed intwo halves by an expansion slot 58 extending axially therethrough. Theexpansion slots 58 are aligned with the respective apexes of the wedgemembers 54 such that the wedge members force the two halves of therespective expansible end portions radially outward as the expansibleportions 56 are slideably displaced inwardly towards each other from adisengaged position with the wedge members to an engaged positiontherewith. The expansible end portions are thus expanded primarily in aradial direction indicated by arrow 60. The expansible end portions alsoinclude ridges 62 thereon to increase the gripping force of the ends ofthe fastener within the respective bores similarly to the firstembodiment.

[0070] An actuator in the form of a spindle 64 is mounted centrallywithin the housing for rotation about an actuator axis 66 which isperpendicular to the longitudinal axis of the fastener assembly as wellthe direction indicated by arrow 60. The spindle 64 includes a raisedcircular protrusion 68 at each end thereof to be received withinrespective mounting apertures in the housing 50 for rotatably mountingthe spindle 64 thereon. The spindle further includes a pair of axiallyspaced and diametrically opposed cams 70, each associated with arespective expansible end portion 56 for displacing the expansible endportions between the respective disengaged and engaged positions as thespindle 64 is rotated.

[0071] A pair of links 72 are coupled between the respective cams 70 andthe associated expansible end portions 56. Each link includes an innerend having an opening therein which defines a cam follower 74 receivinga corresponding one of the cams 70 therein. An outer end of each link 72couples the two halves of the respective expansible end portion thereonat a respective base thereof such that the two halves are resilientlycoupled together. The links 72 act as tension members between theexpansible end portions and the cams 70 for pulling the expansible endportions over the wedges into the engaged position as shown in FIG. 6when the cams 70 are rotated. A portion of the opening of each inner endof the links which faces the expansible end portion associated therewithis arranged to engage the corresponding cam 70 wherein the cam has anincreasing radial dimension at a point of contact as it is rotated fromthe disengaged to the engaged positions so as to pull the expansible endportions inward.

[0072] In use the fastener is installed into a pair of panels asdescribed with reference to FIG. 1 for producing a tight fitting jointtherebetween. In this particular arrangement, as the spindle 64 isrotated by a socket on one end thereof, the expansible end portions arepulled inward towards each other as they are simultaneously expanded forpulling the surfaces 12 to be mounted together towards each other whilethe expansible end portions are gripped within the respective bores 14resulting in a particularly secure and tightened joint.

[0073] A third embodiment of the present invention is illustrated inFIGS. 7 and 8. An elongate tubular housing 80 is provided havingintegral expansible end portions 82. Like the previous embodiment, theexpansible end portions are formed in two halves separated by alongitudinal expansion slot 84. The two halves of the expansible endportions are resiliently coupled together at their respective inner endsby the housing 80. An inner end 86 of each expansion slot 84 isgenerally triangular in shape having an outwardly extending apex whichtapers towards an outer end of the respective slot. The inner ends 86 ofthe respective expansion slots 84 are thus arranged to each receive atriangular shaped wedge member 88 therein wherein the wedge members areoriented with outwardly extending apices so as to mate with the innerends of the respective expansion slots.

[0074] An actuator in the form of a spindle 90 is provided similarly tothe previous embodiment of FIGS. 4 through 6. A pair of links members 92are coupled between respective cams on the spindle 90 and the respectivewedge members 88 so as to slideably displace the wedge members 88 in alongitudinal direction within the respective expansion slots 84. As thespindle 90 is rotated, the cams thereon engage a portion of an openingin the inner ends of the respective link members 92 which faces awayfrom the wedge member 88 associated therewith. Thus as the cams arerotated the cams push the wedges outwardly from the disengaged positionto the engaged position for resiliently deforming the expansible endportions radially outward in a direction substantially perpendicular toan axis of the spindle 90.

[0075] In this arrangement rotation of a centrally located actuator actsto expand respective ends of the fastener assembly within respectivebores in a pair of mating panels without drawing the expansible endportions inwardly such that the fastener assembly is substantially equalin length in both the engaged and disengaged positions thereof.

[0076] A further embodiment of the present invention is illustrated inFIGS. 9 through 11 wherein the fastener 10 includes a fastener assemblyhaving first and second longitudinally extending elements 100 and 102mounted for longitudinal sliding movement with respect to one another.The first and second elements 100 and 102 of the fastener assemblyinclude integral first and second expansible end portions 104 and 106respectively at opposing ends of the fastener assembly. Each expansibleend portion comprises a cylindrical plug having a longitudinallyextending expansion slot 108 extending therethrough to permit expansionthereof in a direction indicated by arrow 110.

[0077] The inner ends 112 of the expansion slots 108 are triangular inshape having an outwardly extending apex such that each slot 108 istapered towards an outer end thereof.

[0078] First and second wedge members 114 and 116 are positionedadjacent the inner ends of the expansion slots 108 of the respectivefirst and second expansible end portions 104 and 106. Each wedge member114 and 116 is a bell shaped member which tapers outwardly for matingwith the respective inner ends 112 of the respective expansion slots108. An opening 120 adjacent the inner end 112 of each expansion slotreceives the corresponding wedge member therein in a disengaged positionwhich permits the two halves of the expansible end portions to remain ina relaxed position having substantially the same diameter as theassembled cylindrical fastener assembly. Sliding each wedge memberlongitudinally outward relative to the respective expansible end portionforces the wedge member into the expansion slot 108 thus expanding theexpansible end portions radially outward in the direction indicated byarrow 110. A pair of levers 121 are formed integrally within thefastener assembly on each side of the openings 120 for mounting therespective halves of the expansible portions thereon such that an innerend of the lever acts as a pivotal mount when flexed as the expansibleportions are expanded. The expansible portions are thus displaced in anarc about the inner end of each lever 121 as they are expanded into theengaged position.

[0079] The first wedge member 114 is mounted on an inner end of thesecond half 102 of the fastener assembly for sliding movement therewithrelative to the first half of the fastener assembly 100. Similarly, thesecond wedge member 116 is mounted on the inner end of the first half100 of the fastener assembly for sliding movement therewith relative tothe second half 102 of the fastener assembly. The wedge members are thusdisplaced into and out of the respective expansion slots 108 by slidingthe two elements of the fastener assembly relative to one another.

[0080] An actuator in the form of a spindle 122 is rotatably mounted onthe fastener assembly between the ends thereof but offset towards oneend for rotation about an actuator axis 123 extending perpendicularly toa longitudinal axis of the fastener assembly as well as beingperpendicular to the direction indicated by arrow 110. Raised circularprotrusions 124 extend axially from the ends of the spindle 122 to bereceived in respective ones of two longitudinal slots 126 located in therespective halves of the fastener assembly. The slots 126 permitlongitudinal sliding movement therebetween while securing the spindletherein for rotary movement. A socket 128 is located at one end of thespindle.

[0081] The spindle 122 carries a pair of axially spaced anddiametrically opposed cams 130. Each cam 130 is received within acorresponding recess 132 located in the respective inner face of therespective half of the fastener assembly 100 and 102 associatedtherewith. Each recess 132 thus defines a cam follower surface forengaging the respective cam 130 associated therewith. The cam profile isarranged to have an increasing radial dimension at a point of contactwith the recess 132 as the cam is displaced from the disengaged to theengaged positions for displacing the halves of the fastener assemblyrelative to one another. Each recess 132 includes a notch 134 in a camfollower surface thereof such that the cam is permitted to rotate pastthe notch 134 when displaced from the disengaged to the engagedposition. Once the cam has been rotated past the corresponding notch 134however, rotation in the reverse direction from the engage position tothe disengage position is restricted by the notch which thus acts as astop.

[0082] A longitudinally extending protrusion 136 is mounted along theinner face of the first element 100 of the fastener assembly and isarranged to be received in a longitudinally extending groove 138 locatedin an inner face of the second element 102 of the fastener assembly. Thegroove 138 is longer than the protrusion 136 to permit longitudinalsliding movement therebetween while providing torsional support betweenthe first and second elements of the fastener assembly.

[0083] The first and second elements 100 and 102 of the fastenerassembly include a central portion of reduced diameter providing agroove receiving an O-ring 140 therein or any other suitable clip forsecuring the elements together. The O-ring 140 snugly secures the firstand second elements of the fastener assembly together while permittinglongitudinal sliding movement therebetween. The section of reduceddiameter of the fastener assembly permits the O-ring 140 to be recessedbelow an outer surface of the fastener assembly.

[0084] A stop 142 in tie form of an annular flange is located at theinner end of one of the expansible end portions for the purposes ofengaging the object in which the fastener is to be mounted and limitingpenetration of the end into the bore in the object.

[0085] The expansible portions each include a plurality of teeth 144extending radially outward. The teeth have penetrating free edges 146 attheir peripheries such that the fins penetrate into the inner surfacesof the bores when the expansible portions are expanded.

[0086] In this arrangement rotation of the spindle 122 causes the cams130 to engage the cam follower surfaces of the respective recesses 132to slide the first and second halves 100 and 102 of the fastenerassembly longitudinally inward such that the wedge members 114 and 116are engaged within the respective expansion slots 108 to expand theexpansible end portions along a plane perpendicular to the axis of therotary cam 122 while simultaneously pulling the respective expansibleend portions inwards towards each other to provide a force which pullstogether a pair of opposing surfaces to be mounted together. The stop142 assists in initially positioning one of the expansible end portionswithin the respective bore. Furthermore the penetration of the teeth 144into the respective bores secures portions of the panel between adjacentteeth as opposed to only frictionally engaging the inner surface of therespective bores receiving the expansible portions therein. The addedgripping force ensures the panels are sufficiently drawn together uponassembly of the fastener with the panels.

[0087] A further embodiment is illustrated in FIG. 12 wherein a pair ofedge bored panels 160 are shown being assembled by the fastener 10. Thefastener of FIG. 12 includes a fastener assembly having two longitudinalhalves 162 similar to the embodiment of FIGS. 9 through 11 wherein thereis provided an expansible portion at one end and a wedge member at theother end of each half of the fastener assembly. The halves 162 arelongitudinally slideable relative to one another for co-operation of thewedge members with the respective expansible portions as describedabove.

[0088] The actuator in the embodiment of FIG. 12 comprises a catch 164which extends radially outward from an outer periphery of one half ofthe fastener assembly. The catch 164 acts as a stop arranged to engagean edge 166 of one of the panels for expanding the expansible portionsinto the engaged position as the panels are displaced towards oneanother. The expansible portion opposite the catch bottoms out in theopposing bore such that the expansible portions are displaced into theengaged position as the panels are pushed together.

[0089] A release aperture 168 is mounted in one of the panels foralignment with one of the wedge members when the panels are coupledtogether such that the wedge member may be released from thecorresponding expansible end portion by insertion of a tool through theaperture to engage the wedge member. The fastener according to FIG. 12is thus selectively separable from the panels by using a conventional orscrewdriver or the like.

[0090] In varying arrangements of the embodiment of FIG. 12 there may beprovided a catch on both halves of the fastener assembly or theexpansible ends may be arranged to bottom out within the respectivebores. In either arrangement the panels engage the halves of thefastener assembly respectively to push them together as the panels arepushed together.

[0091] In a further embodiment as illustrated in FIG. 13, the fastener10 comprises a tubular housing 170 having expansible end portions 172with respective wedge members 174 mounted therein similar to thosedescribed in the first embodiment. An actuator 176 is further providedin the form of a spindle having cams thereon as described above. A pairof link members couple the respective wedge members 174 to the actuatorwherein one of the link members comprises a sleeve 178 and the otherlink member comprises a rod 180 which is arranged to be slideablereceived within the sleeve 178.

[0092] Referring now to variations of the first embodiment shown inFIGS. 1 through 3, the spindle 32 may be a screw which is threadeddirectly into or through the fastener assembly into the surrounding boresecuring the fastener therein. Further arrangements of the pivotal mount38 are also possible to assist in locking the spindle in place oncerotated. This may include a rubber mount, a cam lock, or a ratchetmechanism. The spindle 32 may further be provided with a springmechanism to urge the socket end thereof outwardly beyond an outersurface of the fastener assembly to assist in alignment with theinstallation aperture 42 in one of the panels to be mounted. In yetanother arrangement the spindle 32 may be free rotating within thefastener assembly or provided with a ratchet or clutch mechanism as wellas any other arrangement which would allow one end to expand first or toallow one end to expand more.

[0093] The tension member may comprise any band of material suitable formounting under tension to draw the wedges inwardly while beingsufficiently flexible to be wrapped about the spindle. When mounting thetension member on the wedge members it may be preferable to provide aslot along one side of the wedge members for receiving the tensionmember therethrough for ease of manufacture. Also for ease ofmanufacture it may be preferable to provide a two part fastener assemblyhinged along one longitudinal side thereof for receiving the actuator,the wedge members and the tension member therein. The two part fastenerassembly may be molded as one piece wherein the two halves are hingedtogether by flexing a connecting portion which connects the two halves.

[0094] Referring to the embodiment of FIGS. 9 through 11, the actuatormay be modified so as to remain in a fixed longitudinal positionrelative to one of the halves of the fastener assembly such that onlyone cam 130 is required to engage the other half of the fastenerassembly. In this arrangement, one half of the fastener assembly islongitudinally slideable relative to the other half of the fastenerassembly in response to rotation of the actuator as similarly describedin the embodiment of FIGS. 9 through 11, however the actuator is simplerin design. In either variation of the fastener, the fastener assemblyand actuator comprise only three parts which are simple to manufactureand reliable in construction.

[0095] Referring generally to either embodiment, further modificationsinclude replacing the actuator with a rack and pinion arrangementwherein the pinion is arranged to rotate about the actuator axis and apair of racks are provided which are operatively associated with eachexpansible end portion.

[0096] Although it is preferable to make use of a single standardisedbore size it may be preferable in some instances to have the diameter ofone expansible portion being greater than the other or to have only oneend which expands or one end that expands greater than the other. Thisis particularly useful for on panels which have been manufactured usingdifferent standardised bore sizes.

[0097] The expansible portions may also be formed such that one islonger in length than the other. Elongating one of the expansible endportions is particularly useful when gripping into a panel formed oflightweight material wherein a greater contact area between theexpansible portion and the inner surface of the bore is desired.

[0098] When mounting panels in an edge to edge configuration asillustrated in FIG. 12, it may be useful to offset the actuator towardsone end of the fastener assembly while providing a stop in the form ofan annular flange about the center of the fastener assembly to positionthe fastener 10 evenly within both of the panels.

[0099] Further modifications to the spindle 32 include providing a lockmechanism such as a ratchet mechanism or a material with a coefficientof friction such as a securely fit rubber socket mounting one end of thespindle therein.

[0100] For ease of alignment of two opposing bores and for ease ofinsertion into the bores it may be preferable that an outer diameter ofthe fastener assembly be substantially equal to an outer diameter of theridges surrounding the expansible end portions before expansion thereof.The fastener assembly is thus snugly fit within the bore while theexpansible portions operate as described above. The use of dowels andglue for alignment of the panels is thus not required.

[0101] The outer end of the spindle may include any type of screw heador socket thereon which would permit controlled rotation thereof. Forsimplicity a conventional screw head is preferable such that only theuse of conventional tools is required.

[0102] In order to have more control over the expansion of therespective ends of the fastener assembly, two actuators may be providedwherein one actuator is associated with each expansible end portion ofthe fastener assembly. In this arrangement the fastener may first beinserted into one panel and expanded therein before mounting the secondpanel on an opposite end of the fastener.

[0103] The shape of the wedge members may be generally triangular orbell shaped as well as any other arrangement having a generallydiminishing cross section in one longitudinal direction which defines acamming face operatively associated with the expansible end portions andthe expansion thereof.

[0104] Depending on which particular arrangement or embodiment thefastener comprises, different selections of materials may beappropriate. The materials which form the fastener will generallyinclude zinc castings, steel, plastic or any combination thereof. Anyother material which would allow the fastener to function effectivelywould also be appropriate.

[0105] Referring once more to the accompanying drawings, andparticularly to FIGS. 14 and 15, there is illustrated a fastener 210 forcoupling two objects which are illustrated as being two furniture panels212 and 214. The panels 212 and 214 have respective fastener bores 216and 218 for receiving the ends of the fastener 210. The fastener is anelongate assembly that includes two elongate elements 20 and 222arranged side by side. The assembly has two expandable ends 224 that areportions of the respective elements 220 and 222. Each end is separatedinto two segments 26 by a diametral slot 228 extending longitudinallythrough the end. Spaced along the assembly from the end 224 of element220 is a radially extending stop 229 that limits penetration of thefastener into the fastener receiving bore 218 as will be discussed morefully in the following. Each end 224 of the assembly has a set ofannular teeth 230. Each of the elements 220 and 222 includes a wedge 232that confronts the slot 228 in the end 224 of the other element.

[0106] The element 220 has a transverse through aperture 234 between thewedge 232 and the end 224. This aperture confronts a cavity 236 in theelement 222. To displace the elements 220 and 222 relative to oneanother a lever 238, which may conveniently be in the form of a flatblade screwdriver, is inserted through the aperture 234 into the cavity236 and is then pivoted to provide a prying action on the two elements,driving the wedges 232 into the slots 228 to expand the ends of thefastener assembly. At the same time, this draws the ends of the assemblytogether so that objects engaged by those ends will be drawn together.

[0107] To hold the elements 220 and 222 in the engaged position, withthe ends expanded, the fastener includes a retainer 240. This includes aset of projections, shaped as inclined teeth 242 on the elements 220 anda set of mating recesses 244 on the confronting face of element 222.When the two elements are displaced to the engaged position, the teeth242 are cammed into the recesses 244 by their inclined leading faces andare retained in place by their engagement with the recesses. In orderthat the fastener may be disengaged, an unlock opening 246 is formed inthe elements 220, in the centre of the teeth and communicating with theaperture 234. A confronting groove 248 is formed in the element 222 sothat the lever 238 can be inserted into the aperture 234 and opening 246to engage the groove 248, so that the two elements can be pried apartwhen necessary.

[0108]FIG. 16 illustrates an alternative embodiment of the presentinvention where the fastener 250 includes two elements 252 and 254 withmating faces 256 and 258 inclined to the longitudinal extent of thefastener. Element 252 has a transverse through aperture 60 and element254 a confronting cavity 262 that are used in conjunction with a leverto displace the two elements longitudinally relative to one another,with the two inclined faces sliding along one another to expand thetransverse dimension of the fastener as the elements move from thedisengaged to the engaged position. This embodiment incorporates theretainer mechanism of FIG. 15 for preventing the elements from returninginadvertently from the engaged to the disengaged position.

[0109] A further embodiment of the present invention is illustrated inFIG. 17. In that a embodiment, the fastener 266 has two elements 68 and270 parallel to one another. Each element has a set of teeth 272 on eachof its ends. A spacer 274 is connected to element 270 and is engaged bya screw 276 threaded into a mating bore in element 268. Rotation of thescrew 276 displaces the elements 268 and 270 transversely with respectto one another to enlarge or contract the ends for engaging or releasingthe bores in which they are seated.

[0110] A further embodiment of the fastener as illustrated in FIGS. 18and 19, were the fastener 278 includes two elements 280 and 282, eachwith a diametrically split, toothed end 284 and a wedge 286 at theopposite end which faces towards the end 24. In this embodiment, thewedges work in the opposite direction from those of the embodimentillustrated in FIG. 14, in that they expand the ends of the fastenerassembly from the ends of the assembly towards the centre.

[0111]FIG. 20 illustrates an expansible end for use on one of theelements of a fastener like that illustrated in FIG. 14. In this case,the end 288 has helical teeth 290 which allow the end to be screwed intoan object to which the fastener is to be connected.

[0112]FIG. 21 illustrates a cam mechanism for use in displacing the twoelements 292 and 294 of a fastener between the engaged and disengagedpositions and for retaining the elements in the engaged position. Asillustrated each element has an inclined bore 296 for receiving a cam298. These cams are joined by a shaft 300. The cams and the shaft arerotatable about an inclined axis 302 using a screwdriver engaged in anappropriate screwdriver engaging formation 304 in the end of one of thecams 298. This arrangement makes it convenient to place the actuator camcloser to the intersection between two objects than would otherwise bethe case, that the screwdriver will be inclined away from the junctureof the two parts to be joined.

[0113]FIGS. 22 and 23 illustrate an alternative form of the teeth usedon the ends of the fasteners. As shown, two different toothconfigurations, 306 and 308 teeth are spaced along the end of thefastener and have different profiles providing projecting, triangularteeth to penetrate the surface of the bore when the fastener hasexpanded. As illustrated the stop 310 is larger than the teeth in itsradial extent so as to engage the face of the object to limitpenetration of the fastener into the bore.

[0114]FIG. 24 illustrates a fastener assembly moulded as one piece. Asillustrated, the assembly 320 includes two elements 322 and 324 joinedby a thin, frangible hinge 326 of plastic material. In use, the twoelements are folded together along the hinge and separated when the twoelements are moved relative to one another two the engaged position.

[0115]FIG. 25 illustrates, like FIG. 12, an embodiment of the fastenerthat can be installed without tools. In this embodiment, the fastenerassembly 328 has two elements 330 and 332. Element 330 has an expandableend portion 334 at one end and a radially extending stop 336 at theother. The stop is shaped as an axially extending blade to cut into theface of an object that it engages. The element 332 has an expandable end338. Both expandable ends carry peripheral teeth 340. An actuator 342 ismounted on the expandable end 338, adjacent the inner end. This is aradial stop that engages the surface of an object into which theexpandable end portion 338 is inserted, to limit the depth of insertion.This positioning of the stop or actuator may conveniently be used wherethe bore is on the face of a relatively thin panel, although it is notlimited to use in that environment.

[0116] In other embodiments similar to that illustrated in FIG. 25, theactuator 342 may be omitted, and the stop 336 replaced with a flat stopthat also serves as an actuator.

[0117] While particular embodiments of the present invention have beendescribed in the foregoing, it is to be understood that the invention isnot limited to those embodiments. Other embodiments within the scope ofthe invention are possible. For example, the configuration of theactuators may vary widely, whether configured as cams, stops, screws orsome other mechanism. Cam designs are particularly variable and may beone-lobed or two lobed, depending on whether one or both ends of thefastener are to move relative to the objects being joined in moving fromthe disengaged position to the engaged position. Stops, both forlimiting the depth of penetration and for use as actuators may havevarious forms, depending on any secondary functions they may have, e.g.anti-rotation, and the nature of the material being joined. Wedges mayalso have different configurations. They may, for example be round insome instances to reduce friction. As will be evident to thoseknowledgeable in the in the art, numerous other modifications arepossible within the scope of the invention. All such embodimentsincorporating such modifications are intended to be included within thescope of the present invention. The invention is to be consideredlimited solely by the appended claims.

1. A method of joining two objects with respective fastener receivingbores therein, the method comprising: providing an elongate fastenerassembly with opposite ends, the fastener assembly comprising first andsecond elongate fastener elements arranged side by side; inserting theopposite ends of the fastener assembly into the respective bores; anddisplacing the first and second fastener elements relative to oneanother to expand the ends of the fastener assembly thereby griping thebores.
 2. A fastener for securing together a pair of opposing objectshaving respective bores therein, the fastener comprising: an elongatefastener assembly having first and second expansible portions atrespective ends thereof for being slideably received within therespective bores; first and second wedge members mounted adjacent therespective ends of the fastener assembly for engagement with therespective first and second expansible portions thereof, the wedgemembers and the respective expansible portions being mounted for slidingmovement relative to one another in a longitudinal direction of thefastener assembly between a disengaged position and an engaged positionwherein the wedge members are wedged within the respective expansibleportions of the fastener assembly such that the expansible portions ofthe fastener assembly are expanded in a radial direction relative to thedisengaged position; and an actuator mounted on the fastener assemblyfor rotation about an actuator axis extending transversely to theelongate fastener assembly at a location spaced between the wedgemembers, the actuator being coupled to the wedge members respectivelyfor displacing the wedge members relative to the expansible portionsbetween the engaged and disengaged positions as the actuator is rotated.3. The fastener according to claim 2 wherein the expansible portions ofthe housing are mounted for longitudinal sliding movement relative toone another, the expansible portions of the housing being coupled to theactuator to be displaced towards one another in moving from thedisengaged position to the engaged position.
 4. The fastener accordingto claim 2 wherein the actuator comprises a cam mounted for rotationabout the actuator axis and including a cam follower associated witheach wedge member for urging the wedge members into the engaged positionas the cam is rotated.
 5. The fastener according to claim 4 including anelongate housing and wherein the wedge members are fixed in relation tothe housing and the expansible portions are slideably mounted on thehousing for movement towards each other as the expansible portions aredisplaced from the disengaged position to the engaged position.
 6. Thefastener according to claim 4 including an elongate housing and whereinthe expansible portions are fixed in relation to the housing and thewedge members are slideably mounted on the housing for movement awayfrom each other as the wedge members are displaced from the disengagedto the engaged positions.
 7. The fastener according to claim 4 whereinthe fastener assembly comprises first and second longitudinallyextending elements and wherein the first element mounts the firstexpansible portion and the second wedge member in fixed relation thereonand the second element mounts the second expansible portion and thefirst wedge member in fixed relation thereon, the first and secondelements of the fastener assembly being slideable relative to oneanother for displacing the wedge members relative to the respectiveexpansible portions between the disengaged and the engaged positions. 8.The fastener according to claim 4 wherein the cam includes a pair ofdiametrically opposed camming faces arranged to engage the cam followersassociated with the respective wedge members.
 9. The fastener accordingto claim 2 wherein the wedge members are coupled to the actuator to bedisplaced towards on another in moving from the disengaged position tothe engaged position.
 10. The fastener according to claim 4 wherein atleast one of the cam followers has a profile with a notch therein toresist rotation of the cam from the engaged position to the disengagedposition once the cam has been rotated past the notch.
 11. The fasteneraccording to claim 2 wherein the expansible portions each include aplurality of teeth extending radially outward for penetrating innersurfaces of the bores in the engaged position.
 12. The fasteneraccording to claim 1 including a flexible tension member coupled betweenthe first and second wedge members and wherein the actuator comprises arotatable spindle having an aperture through which the tension member istreaded so that rotation of the spindle about the actuator axis causesthe tension member to be wrapped about the spindle, drawing the wedgemembers longitudinally towards each other.
 13. The fastener according toclaim 12 including a lock for resisting reverse rotation of the spindleand unwinding of the tension member.
 14. The fastener according to claim12 wherein the wedge members are substantially conical in shape and aninner surface of each expansible portion has a mating conical surface.15. The fastener according to claim 14 wherein the conical shaped wedgemembers are oriented such that respective apexes thereof are pointedtowards each other.
 16. The fastener according to claim 1 wherein thehousing is tubular, having a substantially constant diameter betweenrespective ends thereof.
 17. A fastener for securing together opposingobjects having respective bores therein, the fastener comprising: a pairof elongate elements each having a wedge at a first end and anexpansible portion at a second end thereof, the wedge of each memberbeing located adjacent the expansible portion of other member, spacedlongitudinally inward therefrom in a disengaged position, the elongatemembers being slideable relative to one another in a longitudinaldirection of the members from the disengaged position to an engagedposition wherein the wedge of each member is wedged within theexpansible portion of the other member such that the expansible portionsare expanded radially and displaced inwardly towards each other relativeto the disengaged position; and stop means associated with one of theelements for engaging the respective object as the second end of themember are inserted into the bore in the object to limit penetration ofthe expansible portion into the bore.
 18. A fastener according to claim17 wherein the actuator comprises a cam mounted for rotation about theactuator axis for urging the wedge members into the engaged position asthe cam is rotated about an actuator axis.
 19. A fastener according toclaim 18 wherein the actuator axis is fixed relative to said one of theelements.
 20. A fastener for securing together opposing objects havingrespective bores therein, the fastener comprising: a pair of elongatemembers each having a wedge at a first end and an expansible portion ata second end thereof, the wedge of each member being located adjacentthe expansible portion of other member, spaced longitudinally inwardtherefrom in a disengaged position, the elongate members being slideablerelative to one another in a longitudinal direction of the members fromthe disengaged position to an engaged position wherein the wedge of eachmember is wedged within the expansible portion of the other member suchthat the expansible portions are expanded radially relative to thedisengaged position; and stop means associated with each of the membersfor engaging the respective objects as the ends of the members areinserted into the respective bores, whereby on displacement of theobjects towards one another, the objects engage the stop means todisplace the expansible ends inwardly towards each other and into theengaged position thereof. whereby displacement of the objects towardsone another engages the stop means to displace the expansible endsinwardly towards each other with the objects into the engaged positionthereof.
 21. The fastener according to claim 20 wherein the stop meanscomprises a radially extending protrusion on one of the members at alocation spaced between the respective ends of the member.
 22. Afastener for coupling two objects with respective fastener receivingbores therein, the fastener comprising an elongate fastener assemblywith opposite ends for insertion into the respective bores in the twoobjects, the assembly including: first and second elongate elementspositioned side by side and relatively movable between a disengagedposition and an engaged position in which the ends of the fastenerassembly are expanded transversely to engage the respective bores; and aretainer for retaining the first and second elements in the engagedposition.
 23. A fastener according to claim 22 wherein the first andsecond elements are longitudinally tapered and are longitudinallydisplaced relative to one another in movement between the disengaged andengaged positions.
 24. A fastener according to claim 22 wherein thefirst element includes a transverse through aperture and the secondelement includes a cavity confronting the aperture whereby a lever maybe inserted through the aperture to engage the cavity for displacing thefirst and second elements between the engaged and disengaged positions.25. A fastener according to claim 24 wherein the retainer comprises atleast one projection on one of the first and second elements and arecess in the other of the first and second elements for receiving theprojection in the engaged position.
 26. A fastener according to claim 22including an actuator for moving the first and second elementstransversely with respect to one another for movement between thedisengaged and engaged positions.
 27. A fastener according to claim26wherein the actuator comprises an actuator member extending transverselybetween the first and second elements and rotatable about a transverseaxis to vary the spacing of the first and second elements.
 28. Afastener according to claim 27 wherein the retainer comprises theactuator member.
 29. A fastener according to claim 28 wherein theactuator member comprises a transverse threaded number and a matingthread on one of the first and second elements.
 30. A fastener accordingto claim 22 wherein one of the ends of the fastener assembly is largerin transverse size than the other.
 31. A fastener according to claim 22wherein the first and second elements include respective ones of theends of the fastener assembly, each end comprising longitudinallyseparated anchor elements, and wherein the first and second elementsinclude respective expansion wedges, the anchor elements beingpositioned between the wedges in the disengaged position of the fastenerassembly, whereby upon relative longitudinal movement of the first andsecond elements to the engaged position, the wedges engage between andtransversely separate the anchor elements of the respective ends.
 32. Afastener for coupling two objects with respective fastener receivingbores therein, the fastener comprising an elongate fastener assemblywith opposite ends for insertion into the respective bores in the twoobjects, the ends being transversely expandable to grip the respectivebores and each end having teeth on the periphery thereof, wherein theteeth are helically oriented ribs.
 33. A fastener for coupling twoobjects with respective fastener receiving bores therein, the fastenercomprising an elongate fastener assembly including: first and secondelongate elements, the first and second elements having respective firstand second expandable ends for insertion into the respective bores inthe two objects, the first and second elements being movablelongitudinally relative to one another between a disengaged positionwith the expandable ends spaced apart by a first distance and an engagedposition with the expandable ends spaced apart by a second distance,less than the first distance, and the first and second elementsincluding respective means responsive to movement of the first andsecond elements to the engaged position for transversely expanding thesecond and first expandable ends respectively to engage the respectivebores; and a stop on the first element for engaging one of the objectsto limit the depth of insertion of the first expandable end into therespective bore.
 34. A fastener according to claim 33 including a stopon the second element for engaging the other of the objects to limit thedepth of insertion of the second expandable end into the respective bore35 A fastener according to claim 33 including an actuator for moving thefirst and second elements from the disengaged position to the engagedposition.
 36. A fastener according to claim 34 wherein at least one ofthe stops comprises an actuator for moving the first and second elementsfrom the disengaged position to the engaged position in response tomovement of the objects towards one another.
 37. A fastener according toclaim 2 wherein the actuator axis is inclined at an angle less than 90°to the elongate fastener assembly.